Cryo-rolling and annealing tune a dual-phase high-entropy alloy’s strength

A novel high-entropy alloy with the composition Al0.3CoCr1.3FeMnNi0.7 has been pushed through an unusually severe thermomechanical treatment, and the results reveal both the promise and the limits of cryo-rolling as a strengthening strategy for this emerging class of materials. In a comparative study published in the Journal of Materials Science, researchers led by P. P. Bhattacharjee report that heavily cryo-rolling this dual-phase (FCC+BCC/B2) alloy, followed by carefully chosen annealing treatments, produces an attractive combination of strength and ductility: a yield strength of roughly 786 MPa, an ultimate tensile strength near 934 MPa, and about 13 percent elongation to failure.

The Al0.3CoCr1.3FeMnNi0.7 composition is particularly interesting because it stabilizes two phases at once: a face-centered cubic (FCC) phase and a body-centered cubic (BCC) phase that coexists with an ordered B2 structure. This dual-phase character makes the response to deformation and heat treatment more complex than in single-phase systems, and it is precisely this complexity that the new study set out to map.

Cryo-rolling, in which the alloy is deformed while chilled to cryogenic temperatures, progressively built up deformation heterogeneities and an ultrafine to nanoscale lamellar structure. The deformation texture that emerged was a brass-type texture, the signature that the authors associate with alloys of low stacking fault energy.

Annealing below 1000 degrees Celsius transformed the deformed structure into an ultrafine recrystallized grain structure with grains smaller than one micrometer, decorated with profuse Ni-Al-rich B2 precipitates and Cr-rich sigma precipitates. At higher annealing temperatures, the microstructure shifted instead toward a (FCC+BCC) dual-phase configuration. The recrystallization texture itself remained weak, retaining an alpha-fiber component aligned with the normal direction while a large fraction of grains adopted random orientations.

The comparative element of the study is where the findings become sobering. When the tensile properties of the suitably annealed alloy were set against other dual-phase lamellar high-entropy alloys, the strengthening benefit of cryo-rolling appeared subdued. The authors attribute this to the absence of a starting lamellar morphology and to a less favorable precipitation behavior in the present composition. In other words, the same treatment that produces exceptional lamellar architectures in some dual-phase alloys did not translate as effectively here, presumably because the starting microstructure and precipitate evolution did not cooperate in the same way.

Despite that comparative caveat, the measured property balance remains noteworthy. A yield strength approaching 800 MPa combined with roughly 13 percent ductility is a meaningful achievement for a dual-phase high-entropy alloy processed through cryo-rolling and annealing, and the authors highlight the alloy’s integrated cost-performance benefits as a practical advantage. The study thus delivers a dual message: the Al0.3CoCr1.3FeMnNi0.7 system can be tuned to a genuinely useful strength-ductility combination, while the comparison shows that cryo-rolling’s efficacy in this alloy was subdued relative to other dual-phase lamellar high-entropy alloys.

Subject of Research: Cryo-rolling and annealing effects on the microstructure, texture, and tensile properties of a dual-phase Al0.3CoCr1.3FeMnNi0.7 high-entropy alloy

Article Title: Effect of cryo-rolling and annealing on microstructure, texture, and properties of (FCC+BCC/B2) Al0.3CoCr1.3FeMnNi0.7 high-entropy alloy: a comparative study

Article References: Chaitanya, N. K., Paul, S., Yara, R., Saha, R., Vaidya, M., & Bhattacharjee, P. P. (2026). Effect of cryo-rolling and annealing on microstructure, texture, and properties of (FCC+BCC/B2) Al0.3CoCr1.3FeMnNi0.7 high-entropy alloy: a comparative study. Journal of Materials Science. https://doi.org/10.1007/s10853-026-13990-4

Image Credits: AI Generated

DOI: 10.1007/s10853-026-13990-4

Keywords: high-entropy alloys, cryo-rolling, annealing, dual-phase microstructure, B2 precipitates, sigma phase, brass-type texture, recrystallization, tensile properties, materials science, Effect, microstructure